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- (Pea or Bean) family: Fabaceae
Vetch (Vicia spp.)
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Most vetches are annual, cool-season weeds, but winter vetch and hairy vetch can also be biennial or short-lived perennials. They are regularly used as cover crops, forage for livestock, and green manure for soil management, but several species that are not native to California have escaped cultivation; and hence are now considered weeds. The most common weedy vetches include common vetch (Vicia sativa ssp. sativa), narrowleaf vetch (Vicia sativa ssp. nigra), winter vetch (Vicia villosa ssp. varia), purple vetch (Vicia benghalensis), and hairy vetch (Vicia villosa ssp. villosa). Several other native and non-native vetches are also present in California.
Vetches are found throughout California, except for the deserts and Great Basin. Common and narrowleaf vetch are most commonly found below elevations of 1640 feet (500 m) but can survive at elevations up to 4920 feet (1500 m). Hairy vetch and winter vetch can grow at elevations up to 3280 feet (1000 m).
Vetch seeds are toxic to livestock if consumed. The seeds can cause a neurological disorder similar to rabies in cattle and can either kill or stunt the growth of chickens.
Habitat
Vetch grows along roadsides, fences, hedgerows, and the outer edges of woodlands. It also grows in crop fields and field margins, pastures, meadows, orchards, vineyards, uncultivated areas, and other open areas.
Seedling
The first noticeable leaves on the plant are usually the third and fourth leaves—the cotyledons (seed leaves) remain below the soil surface upon germination and the first two or three leaves are also difficult to see. The first leaves that can be seen on vetch seedlings are compound leaves, with leaflets arranged opposite one another on either side of a main stalk. The first seedling leaves typically have 2 or 4 leaflets per leaf. Depending on the species, these leaflets are between 0.2 to 0.8 inch (5–20 mm) long.
A slender, threadlike structure called a tendril may be present at the end of the young leaves. This is more frequently observed on common vetch, narrowleaf vetch, purple vetch but can also be present on winter vetch and hairy vetch.
Mature plant
Mature vetch plants have ridged stems that can grow to be 3.3 feet (1 m) long. They are able to climb over vegetation and other objects and can also form spreading, tangled mats. Leaves alternate with one another on the stems and hold between 8 and 20 leaflets each. Leaflets are between 0.4 and 1.4 inches (1–3.5 cm) long, are creased in the center, and may either be opposite or alternate on the leaf stalk. Leaflets of common, purple, and narrowleaf vetch are linear or elliptical and have a small, distinct point at their tips. Winter vetch and hairy vetch leaflets tend to have broader points. Hairy vetch foliage is always hairy, but the other species vary from hairy to hairless.
Flowers
Vetch flowers are tubular and consist of two main petals—a top petal that is broader at the flower opening, and a narrower bottom petal. Flowers are 0.4 to 1.2 inches (1–3 cm) long and may be various shades of violet, blue-violet, lavender, or white. Flowers of common vetch and narrowleaf vetch are attached to stems and grow in clusters of one to four. Winter vetch, purple vetch and hairy vetch flowers grow on flower stalks (racemes) that may hold anywhere from 10 to 40 flowers each, on only one side of the stalk. Common and narrowleaf vetch bloom from March through July. Hairy and winter vetch bloom from April through July. Purple vetch flowers March through June.
Fruits
Fruits are legumes, or pods, that contain many seeds per fruit. Depending on the species, pods are 1 to 2.8 inches (2.5–7 cm) long and 0.1 to 0.4 inch (0.3–1 cm) wide. Fruits may be flat to nearly round in a cross-section. Their color ranges from tan to black at maturity.
Seeds
Vetch seeds are round or nearly round, and nearly flattened. Their size varies depending on the species, but ranges from 0.1 to 0.3 inches (2.5–8 mm) in diameter. Seed color also varies between vetches, but is generally dark (maroon, greenish gray, brown or black). Occasionally they may be beige or tan.
Reproduction
Vetches reproduce by seed. Seeds typically land a short distance from the parent plant when fruits open, but may also be dispersed by water, soil, animals, agricultural equipment, and in hay as a seed contaminant. Some vetch seeds can persist in the soil for long periods—seeds of hairy vetch, for example, can survive in the soil for up to 18 years. On the contrary, seeds of common vetch are not hard and will not last as long in the soil.
Related species/Similar looking plants
Bird vetch
Tiny vetch
Sparrow vetch
More information
- Broadleaf ID illustration
- For agriculture: UC IPM Pest Management Guidelines
- Calflora's distribution map for common vetch
- Calflora’s distribution map for narrowleaf vetch
- Calflora’s distribution map for hairy vetch
- Calflora’s distribution map for winter vetch
- Calflora’s distribution map for purple vetch